Dragon Tree: what your moisture meter reading means

The healthy band for a dragon tree, on whichever scale your meter prints — and, more usefully, what the same number means in different situations.

Percent (0–100)

22–50%

what the four-in-one we recommend prints

Ten-point probe (1–10)

2–5

if your probe prints a bare 1–10 sweep

Analog dial

1–3

Dry to Wet — of 4 zones

That is the band you are aiming for, not a target to hit exactly. These ranges are published horticultural consensus and are deliberately banded wide — these are unpowered galvanic probes, two of them in the same pot routinely disagree, and fertilizer salt raises the reading with no extra water present.

Got the plant in front of you? Point your camera at it — Plant Tender names what is in the pot from one photo and gives you the numbers it wants. No account, no card.

What each reading means for a dragon tree

A dragon tree wants water below 22% and starts staying wetter than it likes above 50%. If your probe prints a bare 1–10 sweep instead of a percentage, that works out like this.

Reading	For this plant	What to do
1	Bone dry	Well past dry. Water thoroughly now — look for the leaves at the top of each cane going limp and hanging down instead of fanning out.
2	Thirsty	Dry enough to water. Water on the next check unless you watered in the last day or two.
3	In the healthy band	Inside the healthy band. Leave it — the useful question is whether this number is falling since last time.
4	In the healthy band	Inside the healthy band. Leave it — the useful question is whether this number is falling since last time.
5	In the healthy band	Inside the healthy band. Leave it — the useful question is whether this number is falling since last time.
6	Wetter than ideal	Wetter than ideal. Fine a day or two after watering; a concern if it has been a week.
7	Wetter than ideal	Wetter than ideal. Fine a day or two after watering; a concern if it has been a week.
8	Saturated	Saturated. If this has not fallen in several days, check drainage before you change anything else.
9	Saturated	Saturated. If this has not fallen in several days, check drainage before you change anything else.
10	Saturated	Saturated. If this has not fallen in several days, check drainage before you change anything else.

Every row here is worked out from this plant's own numbers — a dragon tree at 4 and a snake plant at 4 are in genuinely different situations.

The number depends on your soil, and most charts ignore that

A dragon tree is usually in dense nursery potting mix, usually with several canes planted together in one pot.

A dragon tree is sensitive to fluoride and salt, and on this plant that sensitivity shows up in two places at once. Salt builds up in the mix from tap water and fertilizer, and it burns the leaf tips brown. The same salt also raises the conductivity of the soil, and a moisture meter is really measuring conductivity, so a salty pot reads wetter than it is. A dragon tree with brown tips and a reading that never seems to fall may not be overwatered at all. It may be sitting in salt.

Adjusting for your mix

Standard mix watered with filtered or rain water: the range on this page applies as printed. Hard tap water or regular feeding: expect readings to creep upward over months with no change in watering; flush the pot by running a large amount of water through it and letting it drain completely, then trust the readings that follow. Perlite-heavy mix: readings run slightly low and the pot dries faster. Fresh mix after a repot: readings often drop compared with the old mix, and that is usually the salt gone rather than the plant suddenly drinking more.

Plant Tender asks which of these your pot is in — dense potting soil, chunky aroid mix, bark / orchid mix, semi-hydro / pon, succulent / cactus grit — and applies the adjustment for you, along with a probe-depth target from your pot size.

Where to put the probe

Halfway down, between the canes and the pot wall. Each cane has its own root mass, and in a pot of three or four canes the space between them is crowded with roots; the soil nearer the wall gives a steadier number. Do not press the probe against the base of a cane. Take readings in the same place each time, because in a salty pot the trend over a few weeks is far more reliable than any one number.

How a dragon tree actually fails

Soft canes. Rot starts at the base, where a cane meets the soil: the bark softens, darkens, and gives when you squeeze it, and the leaves at the top of that cane yellow and drop in a batch. One cane can rot while the others in the same pot stay healthy, so check each one. Two things are regularly mistaken for this. Lower leaves that yellow and fall one at a time as the plant grows taller are normal; that is how the bare trunk forms. Brown tips on otherwise green leaves come from the water or the salt, not from how much you water.

Common situations

My dragon tree has brown tips and reads 5 every time I check.

Those may be one problem, not two. Salt and fluoride from tap water burn the tips, and the same salt raises the reading, so a salty pot can sit at a steady 5 with less water in it than the number suggests. Flush it: take it to a sink or tub, run water through the pot for a few minutes, and let it drain completely. The reading will jump right after, which is expected. What matters is the next week or two: if it now falls steadily through the band, you were reading salt before. Switch to filtered or rain water from here on.

Lower leaves keep yellowing and dropping, and it reads 3.

At 3 the soil is inside the band, so this is most likely the plant growing. A dragon tree sheds its lowest leaves one or two at a time as new ones open at the top, which is how the bare, woody trunk forms. It becomes a problem when leaves drop from the top of the tuft rather than the bottom, when many fall in one week, or when a cane feels soft at the base. If none of those is happening, there is nothing to fix.

One cane has gone soft and the pot reads 7.

That cane is rotting, and on this page 7 is wetter than ideal, so the pot has been too wet for too long. Stop watering and let the reading come down into the band. Squeeze each cane at the base: the soft one needs to come out, but the others may be fine. If the top of the soft cane is still firm and green, cut it off above the rot and root it in water or fresh mix; dragon tree cuttings root readily. After that, water the pot only once it reads 2.

One reading can't be trusted. How fast the pot dries out can.

Everything above is really one argument: a single number from a cheap conductivity probe is not a measurement, it is a data point with a large error bar. Fertilizer salt raises it. Air gaps in chunky mix lower it. Probe depth moves it several points. Two meters in the same pot disagree.

What survives all of that is the trend. The same meter, in the same spot, in the same pot, read over a few weeks, tells you how fast your dragon tree in this specific mix in this specific room actually dries — and that is the thing that answers "do I water it", which no chart can do for you.

Stop looking it up. Point your camera at your dragon tree.

The bands above are for dragon tree in general. Plant Tender gets there from a photo instead: one shot of what is actually in the pot, and it names the plant and gives you the soil-moisture, soil-temperature and light numbers that plant wants. Your first scan needs no account and no card.

Scan a plant — free, no account

Already know what it is? Save it to Plant Tender and it remembers what your dragon tree read last time, then tells you water or leave-it-be — so you are reading a trend instead of interpreting one number in isolation. Free for your first three plants.

Ranges come from Plant Tender's per-species dataset, which is version-controlled and reviewed in public — Dracaena marginata, 22–50% moisture, 61–76°F soil temperature, medium to bright indirect light.